president obama called it a critical first step before adding that the negotiations will in no way weaken the position of the united states. >> if at the end of six months it turns out that we can't make a deal, we're no worse off and, in fact, we have greater leverage with the international community to continue to apply sanctions and even strengthen them. if you ask me what is the likelihood that we're able to arrive at the end state i was just describing earlier, i wouldn't say that it's more than 50/50. but we have to try. >> defense secretary chuck hagel has touched down in pakistan today. the first time in three years a pentagon chief has visited that country. hagel met with their prime minister to discuss tensions over drone strikes and military operations near the border with afghanistan. he spent the weekend in afghanistan visiting u.s. troops. he did not meet with afghan president hamid karzai who is refusing to sign a security agreement with the united states before the end of the year. secretary hagel says it increases the likelihood of a complete u.s. withdrawal. >> you can u